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One of the challenges for designers (beginner and advanced) creating objects for 3D printing is finding software capable of doing the complex things we enjoy seeing in 3D printing news and exhibitions. There really doesn’t seem to be one program capable of doing it all, and this has been re-emphasised to me during my recent studies at MIT and a visit to Autodesk. However, there is some good news: if you’re able to quickly learn software, you can find an increasing number of freebies that seem to be specialising in small aspects of the workflow, which you can move between to create complex designs.

This tutorial will show you how I used completely free software to create a complex object during my time in the MIT course “Additive Manufacturing: From 3D Printing to the Factory Floor” as part of a group project, and is actually very quick once you become familiar with the programs. This particular design combines a hollow object with an internal lattice structure suitable for SLA printing on a printer like the Form 2 from Formlabs, which is what was used for the translucent version in the photo above. The white version in the background is a cross-section view of what is going on within the SLA print.

Step 1: The Overall Form

There are loads of free programs to use for creating 3D models – Tinkercad, Sketchup, Openscad, Sculptris, Fusion 360 (if you’re linked to an educational institution)… there are many more and you can certainly use your favourite. For this project, I actually used Onshape for the first time, which runs completely in the cloud (so no software downloading or limitations on computer operating systems/specifications). If you are at a school or university, you can get a free license. It works very similar to Solidworks or other high-end CAD packages, so if you are familiar with sketches and features, you will pick it up very quickly.

Basically, whichever CAD software you use, you want to create the overall shape of your object. In this case, I created an organic tear-drop shape using a “loft,” and cut a section out of the back so that it would clip onto a desk and act as a bag hook (part of the MIT design challenge).

Step 2: Make it Hollow

Many CAD programs will allow you to “shell” your design, making it hollow inside. However, if you can’t find the tool, or aren’t getting good results, we can do this in the next piece of software. But first, export your solid file as a STL (and if you managed to shell it in this step, export a STL of the hollow version as well and skip the rest of this step. You will still need a solid version for the lattice process).

If you weren’t able to hollow out your design previously, click on Edit>Hollow and set your wall thickness. Just like that, your solid object is now hollow, and can be exported as a STL.

A note for SLA printing:

When using the Form 2 3D printer for the first time, I was surprised to learn that the PreForm software doesn’t allow for the user to specify infill patterns in the same way that is commonly done with FDM printing. That is what created the need for this custom lattice infill, and this tutorial. So, being a liquid resin printer, the final important step is to add drainage holes so that the form doesn’t end up completely full of liquid, and errors don’t occur during printing.

Meshmixer again has this function built in. While in the Hollow tool, you will have the option to “Generate Holes” and manipulate their location. This is really important, as you won’t be able to do it again later once your hollow and lattice are combined (unless you’re familiar with the boolean commands in Meshmixer and manually add a cylinder from the Meshmixer menu to use as a cutting tool).

Step 3: Creating a Lattice

Lattices and 3D printing are best friends. But creating a lattice in many CAD programs is close to impossible, usually requiring advanced skills and a computer that can handle very large patterning features. nTopology Element is a free program that will dramatically simplify the process for you – simply load a STL file, choose a lattice pattern, and boom! your object is now a lattice. But let’s go through it a little more slowly.

1. Import your solid STL file into nTopology Element.

2. On the top menu, click Lattice>Generate

3. In the pop-up, you can play with the lattice patterns (called “Rules”), the size of each lattice volume, and click Generate to get a preview. When you’re happy with the result, click on Apply.

4. You will notice that the result has the lattice coming outside of the original object. This is because only whole lattice volumes are used to fill the object, rather than automatically being trimmed to fit. So we must do this manually. In the top Edit menu, click on the Trim tool. A new pop-up will appear, asking you to select the Lattice geometry and the Trim Volume (original model), which you can select from the drop-down menu on the left. Click apply and the lattice will be trimmed to fit perfectly within your original design.

5. At this point, the lattice is made up of vectors – they have no volume. So the next step is to use the Thicken tool on the top menu to provide a diameter to your lattice.

6. Lastly, the thickened lattice needs to be turned into a single mesh that can be 3D printed. The Mesh button (where it says Interchange on the top menu) will join everything together and give you a single mesh. In the drop-down menu on the left, you can now right-click on the mesh, and click on export to get your STL file.

Step 4: Bringing it all Together

The free version of nTopology won’t let you stitch multiple files together, however the Pro version will if you ever end up with the need for a full license. So back to Meshmixer to bring it all together ready for 3D printing.

1. Import the hollow STL and lattice STL into Meshmixer (when you click on import for the second file, use the Append option).

2. You will notice that the ends of the lattice stick out from your object. There are 2 ways to correct this: Option 1 is to use the sculpt tool with the “Flatten” brush to go around and push the ends of the lattice inside of the object boundary – it’s just like pushing clay.

Option 2 is to ever so slightly reduce the scale of your lattice. With the lattice selected in the pop-up Object Browser window (on the right of my window), click on Edit>Transform and you can either manually manipulate the scale, or more accurately type in the reduction in the transform window (with the uniform scaling option ticked). You should only need a small reduction until the lattice fits just inside the outer skin of your object.

3. By turning off the hollow part in the Object Browser, but keeping it selected, you will get an X-Ray view into your object to check if the lattice and hollow part are intersecting. This can help with any final alignment. Remember; you want the lattice touching the solid shell, but not poking through so it’s visible, or loosely floating within the hollow.

4. In the Object Browser, [shift]+click to select both parts at the same time. A new window will appear that will allow you to Boolean Union or Combine both parts together, creating a single object.

5. Export the final STL and you are ready for 3D printing.

Step 5: Getting Creative

Once you get a bit of experience with this process and some of the other tools in Meshmixer, your imagination is the limit! You can really begin to play with different combinations of solid and lattice structures depending on the result you want. Have some fun and feel free to share any of your own creations in the comments section.

This is yet another example of the need for a unique part – some hooks to display some work in front of my office, which could attach to some vertical plywood fins without permanent fixings like screws or staples. The plywood is 17mm thick, which was the only dimension needed to create this hook design, and I’ve modelled the arms to be a maximum of 17mm apart, with a 1º draft angle to really hold on to the plywood towards the back of the arms which are less than 17mm apart. This creates a good clamping force on the plywood. They are also designed so that they require no support material when 3D printing, making them fast and efficient to produce.

While it’s quite a unique case, I’ve decided to share the design on Thingiverse, Pinshape and Cults in case it’s of use to anyone, or even just a good starting point for your own design. You could even try scaling them in width to fit the dimension of your vertical board. Happy printing.

– Posted by James Novak

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One of the most interesting features of 3D printing is that it’s possible to print multiple parts in their assembled state, reducing the need to bring together a whole range of different pieces and assemble them using screws, snaps, glue etc. While this is normally easier using the Selective Laser Sintering (SLS) process, with a bit of experience and some clever design skills, it’s possible to 3D print moving assemblies on a basic desktop FDM machine.

Pictured above are 2 objects I’ve been wanting to 3D print for a long time as great examples of what can be done with an FDM machine. The first is called an Air Spinner and is free to download from Thingiverse. Due to the tolerances and angles between each part, no support material is needed, and you can literally start spinning each of the pieces straight off the printer, functioning like a gyroscope. A nice quick print, and a great demo piece. Below is a video I found of someone printing and spinning one so you can get the full effect.

The second print pictured to the right is a Planetary Gear Keychain, also free to download from Thingiverse. This one is much more of a test of your printer’s settings, the first time I printed it all of the pieces were completely fused together and impossible to free. Even this print required a knife to separate pieces that formed part of the first layer, with the squished plastic bonding them together as my nozzle was slightly too close to the print plate. This one is remixed from another design on Thingiverse which I recommend you check out for all the instructions to help get the best result, and read how other people achieved successful prints. Here’s a short video to see the planetary gears in action

If you’re looking for some fun prints to share with people, these 2 are very much recommended and relatively quick, although I’m still a very big fan of the Kobayashi fidget cube from one of my previous posts whichis another great assembled object. If you’ve got a favourite 3D printable assembly, leave me a comment/link below and I might add it to my list of things to make!

– Posted by James Novak

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If you’ve been paying any attention to 3D printing over recent years, no doubt you’ve seen at least a few 3D printed prosthetics. From the Iron Man prosthetic arm to the prosthetics being 3D printed for our animal friends, 3D printing is ushering in a new generation of low-cost, customisable prosthetics. Perhaps you’ve even seen my build of the fully robotic InMoov hand which has been documented on this blog.

At the extremely affordable end of the spectrum for humans, Enabling the Future (also called e-NABLE) is one of the most well-known names, developing a range of open source prosthetics since 2013, which can be freely downloaded, printed, assembled and sent off to those in need. As part of my research I have wanted to build one of the e-NABLE hands for a while now to understand more about them, particularly in comparison to the more complex InMoov robot arm. As pictured above, I’ve finally got around to printing the Phoenix v2 hand, which is wrist actuated to open/close the fingers.

When you look at all the details, it really is a clever design which is optimised for 3D printing on a desktop FDM machine, with almost no support material or waste, and tolerances that fit really well together. Anyone with a 3D printer could assemble one of these, most of the non-3D printed parts can be sourced at a local hardware store or found in your shed (screws and fishing line). The instructions are very clear, and there are loads of videos to help demonstrate the assembly process and how some of the technical aspects of the hand work. Because I printed in ABS rather than PLA plastic, the only small hurdle I had was in the thermoforming process of the gauntlet (the bent white piece that mounts to the users arm), which required me using a strip heater in the university workshop. If you find yourself in a similar situation, you can check out the details which were posted in one of my previous posts. However, I recommend using PLA if you have the choice to make this part easier, only requiring some boiling water as demonstrated in this video. In itself, this is a really cool technique that I will use in the future to create stronger parts; you can always learn a lot from 3D printing other people’s designs.

Overall the e-NABLE community really has done a great job in refining this design over the years, and I’m already working on some of my own iterations which will hopefully be fed back into the e-NABLE community in the future. If you’re looking for a project to build and learn from, or potentially getting involved in the community and building hands for people in need, Enabling the Future is definitely worth researching.

– Posted by James Novak

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One of the great opportunities presented by 3D printing is to print multiple parts as a single object, and have them move afterwards as a complete assembly. There are many great examples, and this Kobayashi Fidget Cube has been on my “to-print list” for some time now. The file is freely available on Thingiverse, and it is pretty awesome!

The photos above give some idea of how it works; a series of cubes that are linked, allowing them to rotate around through a series of positions as you fold and open sections of the object. However the video below (not my own) shows exactly how it works, and is basically a form of fidget device that is currently a popular trend.

As well as being a fun object, it is a great test of your printer’s accuracy and settings, and I must admit my Cocoon Create only had average results. The cube works, but some of the movements are much stiffer than the video. This is probably to do with my settings, I was a little impatient in printing so did not optimise as much as necessary things like layer thickness (used 0.2mm and should’ve tried 0.1mm) and printing speed (50mm/s instead of perhaps 30mm/s or less). I also had to use a knife to slice some of the bottom layers where the cubes had fused together on the print plate. Not a bad first effort, but I might try printing again soon to get a really smooth operating fidget cube.

– Posted by James Novak

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Sorry for the blogging silence, this is the longest break I’ve had since starting a number of years ago. Long story short I’ve made a big move recently for work and am only just starting to get back into printing and making new projects. If you follow my social media, you’ve probably noticed some new things starting!

One of the projects I’ve wanted to play with since previously building the InMoov robot arm is the Enabling the Future prosthetics (aka. e-NABLE). This week I 3D printed and built most of the Phoenix v2 hand, which of course is open source and free to download. A really inspiring company, and a vastly more simple design compared to the electronic InMoov! Some of the pieces, which I printed on an UP Mini 2 in ABS plastic, can be seen above. I’ll post full details once I get it up and running, just waiting on some elastics for the fingers. The gauntlet piece, which attaches to the users forearm, is printed in a flat position and then bent into a C shape afterwards. This is a really clever idea for providing the strongest functional part with optimal layer orientation. But how do you bend a 3D print?

Well the instructions from e-NABLE require dipping the piece in boiling water for a few seconds to make it pliable – if you 3D print in PLA, which has a lower melting temperature than ABS. Check out the video here. However ABS is not really going to be affected by boiling water, and just to make sure I did try this technique with my first print. It did get a bit of a bend, but mostly a snap!

For print #2 I instead found myself a strip heater in the workshop, which is perfect for heating a nice clean line and normally used to bend acrylic sheets. A few seconds on each side of the print and it bent perfectly without de-lamination or splitting, and was easy to re-heat to make small adjustments to fit with the hand print. This is a technique I’d never thought of using, but has really given me a lot of ideas for creating 3D prints which are post-processed like this into a stronger shape than if they were 3D printed in their final more complex form. I think some of the simple enclosures I’ve made in the past could be much stronger if considered more like a sheet-metal part, although then this begs the question why not just laser cut the design? Well in the case of this e-NABLE prosthetic, there are some 3D details for snapping in other pieces, which could not be done using a 2D process like laser cutting. This would be important to consider if using this process with 3D printing, but it’s certainly an interesting technique worth further experimentation.

If you’ve done something like this yourself, or have ideas for thermoforming a 3D print, leave me a comment.

– Posted by James Novak

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Recently I wrote a step-by-step tutorial for my friends at Pinshape about how you can use free software (Meshmixer) to combine downloaded STL files into your own unique design – this is called a mashup, or a remix. The tutorial is nice and easy to follow, and was just the start of my plan to create some really interesting designs in a series of mashups. You can find a full video tutorial and links to the written tutorial in my previous post.

Finally I’ve found some time to create mashup number 2, Mashup-Yoda! This design has taken a lot more time to create in Meshmixer, along with learning some of the more advanced tools and plenty of trial-and-error along the way. However it is based on a similar idea as the Mashup-Rex from the tutorial, combining a skeleton element with an external skin to give a cutaway effect to the creature. However, what might Yoda’s skeleton look like?

As you (hopefully) know from the film Return of the Jedi, Yoda’s body vanishes as he becomes one with the force in his death, so there is no way to know. But upon finding the Voronoi Yoda model by Dizingof on Thingiverse, it seemed like an interesting concept for this powerful Jedi, perhaps a more organic internal skeleton that was formed by the Midi-chlorians (some real Star Wars nerd talk!) that gave Yoda his power.

Nerd talk aside, as much as anything the Voronoi Yoda just seemed like a cool model that would be fun to combine with a realistic bust of Yoda, also available freely on Thingiverse. The 2 models are a great fit, with the main challenge being the slicing and dicing of the geometry in Meshmixer to create this organic looking, almost cyborg-like Yoda mashup. Mostly this has been achieved using the Sculpt tools and the Select tool to remove sections of the models and re-shape them to look like they were designed this way from the beginning.

I’ll admit that I did have some problems combining the 2 models into a single STL file right at the end in Meshmixer, probably due to the weird intersections between the models where I had pushed and pulled surfaces too far into a non-manifold object. I also ended up with a file size of about 87MB, a bit ridiculous for sharing online, and the normal reduction techniques in Meshmixer were just destroying the quality of the surfaces. So I ended up bringing the large STL file into Rhinoceros, reducing the mesh by about 75%, exporting as a STL, importing back into Meshmixer, using the Inspector tool to repair any little remaining errors automatically, and finally exporting a clean, 3D printable STL file. That’s a mouthful!

Now that the hard work’s been done, I’d love you to have this model for free so you can print it out, or even get crazy and try remixing my remix using some of the techniques shown in my Pinshape tutorial! I’ve uploaded it to my favourite 3D file sharing websites Pinshape, Thingiverse, 3D File Market and Cults. Choose your website, 3D print and share some photos 🙂

May the force be with you

– Posted by James Novak

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The mashup is a favourite technique in the music world that combines two or more songs together into a single song. They might be from completely different eras or genres and when cleverly mashed together, they create a new smash hit. But did you know that creating a 3D printable mashup is just as easy as creating a musical one? Take a bit of File A, mix it with File B, and you now have your own creative design.

Over the last few weeks I’ve been putting together a new tutorial for my friends at Pinshape, which includes my first video tutorial as well as the usual step-by-step process to follow along with. Click here to learn how to mashup STL files in only 10 easy steps using the freely available software Autodesk Meshmixer.

The mashup is often called a Remix in the 3D printing world, and is a great way to build upon other designs and add your own creative touch, or re-purpose a design for a new application. The video tutorial is a real-time look at the process, which with a bit of practice, will have you remixing new designs in a matter of minutes. If you want to follow along, you just need to install Meshmixer on your computer, and download the 2 T-Rex files used in this tutorial which are free on Pinshape:

Alongside the tutorial is my latest design, the Mashup-Rex. I have made this available for free on Pinshape, just click here to download the file. Maybe you you will create your own remix of my remix? If you do, or you just 3D print the Mashup-Rex for yourself, please share it on Pinshape to add to the community and see how far the design can go! In the version pictured above I simply used a coffee stain to “age” the skull, similar to my previous print of the Star Wars Deathtrooper. I’m enjoying this simple technique at the moment, although you may like to use a 2-tone print, or go all out with some painted effects.

From a technical standpoint my print isn’t perfect with the wall thickness far too thin, leaving some holes and messy details (eg. if you look closely at the eye socket of the skull). My new Cura settings still need some tweaks. However given all the hurdles, it’s still a pretty damn cool print that is really brought to life by the addition of a bit of black paint, and a simple coffee stain for the skull. I recommend checking out the original by Paul to see all the details of the design that aren’t captured well in my print, he’s done a brilliant job of finishing his print to give it an aged bronze look that shows every little scar and crack of the smashed Stormtrooper helmet.

If you want to make one for yourself, don’t forget to upload a photo of your 3D print to Pinshape by May 12th – there is a competition to win 1 of 40 rolls of filament (ABS or PLA) or some Resin if you use an SLA printer. You get an entry for every 3D print you upload of anything on the website!

– Posted by James Novak

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Designing your own 3D printable object can be daunting if you’ve never used a 3D CAD program before. This is a challenge that one of my university classes is facing, with most of the students new to 3D design, but eager to begin experimenting with 3D printing. So this week we explored a workflow that allows them to take their hand-drawn sketches through a couple of simple processes, resulting in a 3D printable file, without having to model in 3D from scratch. So here it is just for you – follow along and let me know how you go.

Step 1: The Sketch

This is the easy part! Find a sketch that you’d like to turn 3D. It’s best if it’s drawn clearly in pen, so if your sketches are in pencil just trace over them on a fresh sheet of paper. For this example I’m borrowing a sketch from online. You must then digitise your sketch – best using a flatbed scanner, or take a photo in good lighting conditions so you get good contrast between your linework and paper.

Step 2: Vectorising

We are going to use Adobe Illustrator to automatically trace the outlines of our sketch. Place your sketch into a new document, and you will see a “Live Trace” or “Image Trace” button appear (depending on your version of Illustrator) near the top menu. You may find that one of the preset options will give you an accurate tracing, or you will need to get into the options and start tweaking the settings. I have an older version of Illustrator, but the settings that work for me are shown above. What you are looking to achieve is a good level of detail, and nice closed lines. Once you have a good result, you can use the “Expand” button to turn the result into individual lines that can be selected. You can also go to the menu and select Object>Ungroup so that your linework is no longer all grouped together as a single item.

Step 3: Exporting

If you have a collection of sketches like this example, you will want to now Save your file (so you can come back to it and make changes later on), and then delete everything from the file that you don’t want to turn 3D. For this example, I have just left the flower tracing that was in the top-right corner. Go to File>Save As and save this drawing as a SVG file. This is a 2D drawing format that will be recognised by our 3D software.

Step 4: Going 3D

For this example we are going to use the freely available 3D software Tinkercad – one of the best features being that it runs from your internet browser, no need to download and install anything. I recommend it as a great place to start your 3D modelling journey, however if you’re already using a more advanced 3D CAD program you can still follow along with this tutorial – the process will be quite similar.

Create a new Tinkercad file, and at the top right of the workspace is the “Import” button – select your SVG file and it will automatically be turned into a 3D object as shown above. Depending on your sketch and requirements, this might be all you need to do and you can jump straight ahead to Step 7: Exporting. However I want to make some modifications to this design now that I have a good starting point in 3D.

Step 5: Modification

For my needs this object is too thick – I only want it to be 2mm tall. In the right panel of objects is a translucent box – this box is like a cutting tool, anywhere it touches my 3D object it can be used to cut away at it. Place a box in the middle of your 3D model, and use the Length and Width sliders to fully enclose your 3D model. Lastly, rotate your model to a side view and you will see an arrow pointing up or down – click-and-drag on this to move the box up 2mm above the workplane.

Now select both the 3D model and the box (either click-and-drag a selection box around the workplane or hold the Shift button and select both objects) and you will notice at the top right the Group icon becomes available. Click on this and Tinkercad will subtract the box from the 3D model, leaving just a 2mm thick object.

Step 6: Patterning

Rather than just printing one of this design, I want to create a more complex pattern. Firstly I need to scale the design down so that it’s a bit smaller. Do this by clicking on the object, holding the Shift button and using the corner handles to click-and-drag the object down in size – mine is about 40x40mm.

With my object selected, at the top left of the window are the standard Copy and Paste actions, as well as the Duplicate option – this is the option I use to make copies. It may copy the object in the exact same position as the original, so when you click Duplicate just click-and-drag this copy out into a new position. Repeat as many times as you like to create a pattern.

When you’re happy with the design, you will need to join all of these individual elements together into a single object. Similar to step 5, select all the objects together and the Group button will become active – however because all of these objects are solids, the Group function will join them together rather than cutting away.

Step 7: Exporting

When your design is complete, use the Export function at the top right of the window to download the object to your computer. The STL option is most likely what you will want for 3D printing. The STL format is the standard file type for all 3D printers.

Step 8: 3D Printing

Finally you can load your STL into your 3D printing or slicing software and 3D print! If the print doesn’t give you the result you want you can either go back to the Tinkercad file and make some more modifications in 3D, or take a step further back to Illustrator and modify the original linework.

The process is not perfect or overly accurate, however for designs like fashion or simple experiments, this can be a good workflow to try if you’re better/faster at drawing by hand than modelling directly in 3D software. If anyone has some different workflows they enjoy using, please feel free to share them in the comments section 🙂